The OpenStreetMap project collects an amazing amount of geodata and makes it available to the world for free. But the raw OpenStreetMap data is hard to use. On this web site you'll find some of that data pre-processed and formatted for easier use.
Pre-processing includes removing or fixing of wrong data and assembling of different parts of the data into a usable whole. The data is formatted into Shapefiles for easy use in the usual GIS applications.
The following data sets are available from this site:
Coastline data processings
Polygons for all land areas in the world, ie. continents and islands.
Polygons for oceans and seas.
Linestrings for coastlines.
Antarctic icesheet polygons
Polygons for ice covered areas in Antarctica that are not explicitly mapped as glaciers.
Antarctic icesheet outlines
Outlines of ice covered areas in Antarctica that are not explicitly mapped as glaciers.